ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    The cationic polymerization of N-vinyl-2-pyrrolidone initiated electrochemically by anodic polarization on a Pt surface (1994)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 32 (1994), S. 1551-1555 
    Details
    ISSN: 0887-624X
    Keywords: poly(vinyl pyrrolidone) ; cationic polymerization ; electropolymerization ; thin films ; surface modification ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The electroinitiated polymerization of N-vinyl-2-pyrrolidone has been investigated. After electrolysis at controlled potential, a thin, covering, and homogeneous film of poly(N-vinyl-2-pyrrolidone) appears on the electrode. The insolubility of the polymer in its classical solvents implies the existence of a true chemical grafting of macromolecules on the platinum surface. Chain propagation occurs by a cationic mechanism initiated by a direct electron transfer leading to grafted cations on the surface, followed by the nucleophilic attack of neutral molecules. The molecular weight of the polymer was estimated by gel permeation chromatography after having mechanically removed the film from the electrode. A molecular weight distribution curve showing an average value of 16,000 was observed. © 1994 John Wiley & Sons, Inc.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1994.080320816
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Spectroscopic studies of a metallic surface modification by grafting and growth of a polymeric film (1990)
    Chichester [u.a.] : Wiley-Blackwell
    Surface and Interface Analysis 16 (1990), S. 425-426 
    Details
    ISSN: 0142-2421
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/sia.740160188
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Study of the Silicon/γ-APS/Pyralin Assembly Interfaces by X-ray Photoelectron SpectroscopyPaper presented at the 4th International Conference on Adhesion and Surface Analysis, 16-18 April 1996, Loughborough, UK (1996)
    Chichester [u.a.] : Wiley-Blackwell
    Surface and Interface Analysis 24 (1996), S. 774-780 
    Details
    ISSN: 0142-2421
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Polyimides have been extensively studied in view of their wide industrial applications. Adhesion to a substrate is essential for normal operation of devices. This problem is often solved by the use of an adhesion promoter on the surface of interest. A surface-sensitive technique such as XPS has proved to be a powerful analytical tool for the analysis of the polymer/substrate interface. In the present paper, the interfaces of the SiO2/γ-aminopropyltriethoxysilane (γ-APS)/Pyralin system have been investigated at a precured stage. A detailed analysis of the molecular structures formed at the interface is carried out using XPS spectroscopy. An attribution of the various peak components is made with the help of accurate calculations of presumed core-electron binding energies using a recent procedure based on the Density Functional Theory. Two acid-base mechanisms are described. The first one occurs between the ammonium end of the γ-APS molecule and the silicon surface hydroxyl (NH3U+SiO-), whereas the second one is formed between the ammonium end of the γ-APS and the polymer carboxylic function (NH3U+COO-). The results at the first interface are in contradiction with the expected stable oxygen-bridged bond (siloxane), thus the rearrangement of the γ-APS molecule upon heating, as suggested by Linde in a dynamic ‘Flip model,’ has been studied.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
  • 4
    Electronic Resource
    Electronic Resource
    UPS and XPS study of the polymer/metal interface of poly(2-methyl-2-propenenitrile) electropolymerized on an oxidized nickel surface cathode (1992)
    Chichester [u.a.] : Wiley-Blackwell
    Surface and Interface Analysis 18 (1992), S. 443-447 
    Details
    ISSN: 0142-2421
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Mechanisms of formation and structure of the interface between an oxidized nickel surface and poly(2-methyl-2-propenenitrile) obtained by electropolymerization under cathodic polarization are studied by UPS and XPS spectroscopies. The results suggest that a direct interaction takes place between the monomer molecules and surface metallic sites freed by reduction of the metal oxides. The interface between the metal and the resulting polymer is characterized by the existence of chemical bonds of the carbon-nickel type.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/sia.740180612
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Tribological behaviour of heat-treated thin films of electropolymerized polyacrylonitrile (1994)
    Chichester [u.a.] : Wiley-Blackwell
    Surface and Interface Analysis 22 (1994), S. 393-397 
    Details
    ISSN: 0142-2421
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Thin films of polyacrylonitrile (PAN) grafted on nickel have been studied as a substitute for gold coating of low-level semi-permanent electric contacts. Various heat treatments were performed to diminish the electrical resistivity of the layer. In this paper we describe the tribological properties of the treated films submitted to reciprocal wear tests. These tests are performed with ball/plane contacts with the PAN film deposited on the plane. XPS analysis of the heat-treated layers shows the evolution of the composition with both temperature and duration of the treatment. Auger analysis is then used as a tool to analyse the failure mode of the layer. The results show that a first stage of wear can be described as a slow decrease of the PAN thickness. Metal/metal junctions are then initiated and lead to the onset of failure. Heat treatment is shown to improve the mechanical behaviour of the layer up to a limiting value imposed by the brass substrate.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/sia.740220185
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Spectroscopic studies of the interface built up during the formation of an electropolymerized polyacrylonitrile thin film on a copper surface cathode (1993)
    Chichester [u.a.] : Wiley-Blackwell
    Surface and Interface Analysis 20 (1993), S. 468-474 
    Details
    ISSN: 0142-2421
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: We present in this work a series of result obtained on the atmospherically oxidized copper-acrylonitrile system, our aim being to follow the deposition, by grafting and growing, of electropolymerized polyacrylonitrile film. Combining analytical means of electrochemistry - XPS, UPS and infrared reflection adsorption spectroscopy (IRAS) - allows quite an accurate description of this phenomena.The film was deposited by the imposition of a linearly growing negative tension to the copper electrode dipped in an electroyltic solution containing acrylonitrile. The polarization is stopped at different potentials of the current-potential characteristic. These potentials correspond to the formation steps of the interface. Thus we describe, successively, the nature of the initial states (atmospherically oxidized copper) and the final states (insulating and covered polyacrylonitrile thin film of 20-30 Å) in relation to the change in density of occupied electronic superficial states.The appearance of this insulating and covering film is expressed on the current-potential characteristic by an inhibition peak, named and passivation peak.Moreover, the non-stoichiometric character of the superficial copper oxide is identified and permits the use of a low electrochemical potential (before the oxide electroreduction potential) to graft the polymer onto non-oxidized sites.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/sia.740200521
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...